[The fusion and expression of genes encoding heat-stable and heat-labile enterotoxins of escherichia coli from porcine origin]

Abstract

The genes encoding precursor heat-stabile (pro-ST) and mature peptide of B unit of heat-labile (LT) enterotoxins of Escherichia coli from piglet were amplified by polymerase chain reaction (PCR). The 3' terminus of gene encoding pro-ST was genetically fused to the 5' terminus of the LTB subunit gene in nest-PCR. The fusion genes encoding pro-ST and LTB were cloned into pGEM-T vector and subcloned into the pQE30. The recombinant plasmid was expressed in E. coli by IPTG induction. The fusion protein possessed both ST and LTB antigenicity, as well as it had lost the biological toxicity of ST or LT toxin.